It is well known that DNA in some microbes, for example some streptomycetes, contains genes responsible for antibiotic synthesis. Attempts to clone such DNA into a suitable host, for example, E. coli HB101, has not heretofore been accomplished. It is believed that the presence of lethal gene(s), i.e., gene(s) responsible for antibiotic synthesis, interfere with the cloning process. It is recognized that there may be other factors which prevent the successful cloning.
The process of the subject invention solves the above problem by fragmenting the DNA prior to cloning the DNA into a suitable host. The DNA described herein is essentially pure plasmid pUC3 which is obtainable from a biologically pure culture of the microorganism Streptomyces sp. 3022a, NRRL 11441. Plasmid pUC3 has a molecular weight of approximately 20.times.10.sup.6 daltons.